Saab has launched a new 9-3 variant which also heralds the arrival of lower emission turbodiesel engines.

The 9-3 Turbo Edition comes in saloon and SportWagon estate bodystyles and with extra equipment levels as standard, including 17-inch alloy wheels, leather seats, heated front seats, dual-zone climate control, MP3-compatible stereo and cruise control.

Under the bonnet is a choice of engines from Saab’s revised EcoPower diesel engine range.

The 1.9-litre TiD with 150bhp has its CO2 emissions reduced from 151 to 137g/km, a fall of three benefit-in-kind tax bands, while claimed combined fuel economy rises from 49.6 to 54.3mpg.

The 180bhp 1.9-litre TTiD twin-turbo diesel sees emissions fall from 149 to 139g/km – a drop of two BIK bands.

Fuel economy rises from 50.4 to 53.3mpg on the combined cycle.

Also available is a turbocharged 1.8-litre petrol unit and the 120bhp diesel carried over from before, plus the option of an automatic gearbox.

The improvements have been made by the fitment of revised gearboxes with ratios optimised for fuel efficiency, a re-mapped engine control unit and low rolling resistance tyres.

Prices for the Turbo Edition start at £19,995 for the saloon and £21,071 for the SportWagon.

Porsche has announced two new Cayenne SUV models – a diesel version and a petrol-electric hybrid.

The diesel uses the Volkswagen Group 3.0-litre V6 engine which develops 240bhp. Porsche claims average fuel consumption of 30.4mpg and CO2 emissions of 244g/km. Prices start at £39,404.

The Cayenne S Hybrid, which goes on sale in 2010, is powered by a supercharged 3.0-litre direct injection V6 petrol engine borrowed from the Audi S4, developing 333bhp and allied to a 52bhp electric motor which can operate as a slave motor to the petrol engine to provide extra acceleration, or power the car independently.

A new development is the ‘sailing’ mode which allows the car to be driven by the electric motor at speeds of up to 86mph.

Despite the high power output and the vehicle’s size and weight, Porsche claims CO2 emissions of less than 210g/km and 0-62mph acceleration in 6.8 seconds.

Elsewhere, Renault has announced prices for its revised Clio range. Prices start from £9,995 and rise to £14,645 for the 38-strong range of three and five-door hatchback and estate models.

The new Clios, which feature revised front-end styling, arrive in showrooms next week.

Also in the supermini sector, Seat has added a new common rail diesel engine to its Ibiza range. The 1.6-litre TDI unit develops 105bhp and returns a claimed 67.2mpg and emits 109g/km of CO2.

The new engine is available in Sport trim on three and five-door versions.

Prices will be announced closer to the model’s July on-sale date.